@misc{cryptoeprint:2015:611,
author = {Shijun Zhao and Qianying Zhang},
title = {A Unified Security Analysis of Two-phase Key Exchange Protocols in TPM 2.0},
howpublished = {Cryptology ePrint Archive, Report 2015/611},
year = {2015},
note = {\url{http://eprint.iacr.org/}},
}
You will need the url.sty package (comes with most LaTeX installations) for the last line. Otherwise, remove the \url command.